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We report the suppression of nucleation in the nonphotochemical laser-induced nucleation of supersaturated aqueous potassium chloride solutions when the system pressure is above ambient pressure. The crystal yield at 51.7 bar is reduced to 5% of its value at 1 bar, and the crystal number dependence on pressure fits well to a semiempirical model based on the impurity-heating mechanism and the adiabatic compression of an ideal gas nanobubble. Our results complement recent findings by Barber and Alexander [] using high-speed imaging of bubbles preceding the observation of cesium chloride crystals. Together, these two studies provide compelling evidence for the impurity-heating mechanism. 

Elected officials have privileged roles in public communication. In contrast to national politicians, whose posting content is more likely to be closely scrutinized by a robust ecosystem of nationally focused media outlets, sub-national politicians are more likely to openly disseminate harmful content with limited media scrutiny. In this paper, we analyze the factors that explain the online visibility of over 6.5K unique state legislators in the US and how their visibility might be impacted by posting low-credibility or uncivil content. We conducted a study of posting on Twitter and Facebook (FB) during 2020-21 to analyze how legislators engage with users on these platforms. The results indicate that distributing content with low-credibility information attracts greater attention from users on FB and Twitter for Republicans. Conversely, posting content that is considered uncivil on Twitter receives less attention. A noticeable scarcity of posts containing uncivil content was observed on FB, which may be attributed to the different communication patterns of legislators on these platforms. In most cases, the effect is more pronounced among the most ideologically extreme legislators. Our research explores the influence exerted by state legislators on online political conversations, with Twitter and FB serving as case studies. Furthermore, it sheds light on the differences in the conduct of political actors on these platforms. This study contributes to a better understanding of the role that political figures play in shaping online political discourse. 

ABSTRACT AimSurveying the demography of populations near species range edges may indicate their vulnerability to range contractions or local extinction as the climate changes. In the rocky intertidal, not only are latitudinal ranges constricted by thermal stress, but tides also create zonation or a ‘vertical range’ driven by sharp environmental gradients. By investigating demographics along the latitudinal and vertical ranges simultaneously, we can investigate whether populations may be vulnerable to a changing climate. LocationRocky intertidal habitats along west coast of the United States. TaxaOchre sea starPisaster ochraceus, six‐armed sea starLeptasteriasspp., emarginate whelks(Nucella ostrina and N. emarginata) and channeled whelkN. canaliculata. MethodsIn 2018, we surveyed the demographics of the taxa above at 33 sites spanning > 11° latitude from central Oregon to southern California, near the southern range limits of each taxon. We counted and sized individuals from the high to low intertidal zone. To understand how environmental stress changed with latitude, we evaluated intertidal temperaturesin situ, as well as tidal extremes, tidal amplitude and wave exposure using offshore buoys. ResultsFor all taxa, population density, the relative proportion of smaller individuals (except for emarginate whelks) and the upper vertical limits on the shore declined from north to south as temperatures increased and high tide height, tidal amplitude and wave heights decreased. In addition, smaller individualLeptasteriasspp. generally inhabited lower shore levels while smaller individual emarginate whelks inhabited higher shore levels coastwide. ForN. canaliculata, smaller animals were higher on shore northward, but lower on shore southward. Main ConclusionsWhile this study is a snapshot in time and cannot assess impacts of climate change, our surveys suggest environmentally‐related demographic limitation toward southern range limits and demographically vulnerable southern populations. Therefore, a warming climate may cause local extinctions or range contractions near southern limits. 

SimulaTE is studying teaching simulations as formative assessments of pre-service teachers’ (PST) practice of eliciting and interpreting students’ mathematical thinking. Preparation and protocols that promote reliability and validity of the simulations as formative assessments will enhance their effectiveness and generalizability. Teacher educators who use the simulations document each PST’s performance to generate feedback for the PST in nine categories, arising from a decomposition of the teaching practice into specific component skills or actions. A series of coordinated validation studies include research to determine if the nine categories are distinguishable through the use of the simulation assessments, and can benefit from attention beyond other experiences PSTs have in their teacher preparation programs 

This is for a highlight of the application-oriented numerical computation and optimization-a celebration of 60 years of the IJCM publication. On a usual rainy day in early May 1964, the first issue of the International Journal of Computer Mathematics (IJCM) was published in London, Great Britain. Apparently, mathematicians around the world felt and were excited by the morningtide and shock waves from digital computations, after the success of modern computer hardware configuration and software structures. The twilight of the digital new age inspired the pioneers, and this also led to the birth of the IJCM, even before the invention of the word numerical analysis. The first volume of the IJCM consisted of 4 issues, 314 pages of 16 peer-reviewed research papers, and 4 book reviews. 

Despite the long-standing calls for increased levels of interdisciplinary research as a way to address society’s grand challenges, most science is still disciplinary. To understand the slow rate of convergence to more interdisciplinary research, we examine 154,021 researchers who received a PhD in a biomedical field between 1970 and 2013, measuring the interdisciplinarity of their articles using the disciplinary composition of references. We provide a range of evidence that interdisciplinary research is impactful, but that those who conduct it face early career impediments. The researchers who are initially the most interdisciplinary tend to stop publishing earlier in their careers—it takes about 8 y for half of the researchers in the top percentile in terms of initial interdisciplinarity to stop publishing, compared to more than 20 y for moderately interdisciplinary researchers (10th to 75th percentiles). Moreover, perhaps in response to career challenges, initially interdisciplinary researchers on average decrease their interdisciplinarity over time. These forces reduce the stock of interdisciplinary researchers who can train future cohorts. Indeed, new graduates tend to be less interdisciplinary than the stock of active researchers. We show that interdisciplinarity does increase over time despite these dampening forces because initially disciplinary researchers become more interdisciplinary as their careers progress. 

Government spending on artificial intelligence (AI) has surged across the world. Quantifying the return on research investments is notoriously difficult, especially in newly emerging economic sectors. Here, we propose a novel way to describe and analyze where AI ideas are being used and how they spread—by tracing the people and academic communities involved in AI research as they transition from government-funded research labs to private sector companies, carrying cutting-edge “AI know-how” with them. Linking existing university administrative data with state employment records allows several quantifiable inferences about the value of AI research to be drawn from these academia-to-industry migrations. Here we describe a pilot implementation of this system, which is being developed in the State of Ohio. It offers a template for governments and policy makers all over the world. Importantly, the metrics discussed below offer a way to measure the economic impact of scientific research in general, with implications for critical and emerging technologies that go far beyond AI. 

A powerful way to predict how ecological communities will respond to future climate change is to test how they have responded to the climate of the past. We used climate oscillations including the Pacific Decadal Oscillation (PDO), North Pacific Gyre Oscillation, and El Niño Southern Oscillation (ENSO) and variation in upwelling, air temperature, and sea temperatures to test the sensitivity of nearshore rocky intertidal communities to climate variability. Prior research shows that multiple ecological processes of key taxa (growth, recruitment, and physiology) were sensitive to environmental variation during this time frame. We also investigated the effect of the concurrent sea star wasting disease outbreak in 2013–2014. We surveyed nearly 150 taxa from 11 rocky intertidal sites in Oregon and northern California annually for up to 14-years (2006–2020) to test if community structure (i.e., the abundance of functional groups) and diversity were sensitive to past environmental variation. We found little to no evidence that these communities were sensitive to annual variation in any of the environmental measures, and that each metric was associated with < 8.6% of yearly variation in community structure. Only the years elapsed since the outbreak of sea star wasting disease had a substantial effect on community structure, but in the mid-zone only where spatially dominant mussels are a main prey of the keystone predator sea star,Pisaster ochraceus. We conclude that the established sensitivity of multiple ecological processes to annual fluctuations in climate has not yet scaled up to influence community structure. Hence, the rocky intertidal system along this coastline appears resistant to the range of oceanic climate fluctuations that occurred during the study. However, given ongoing intensification of climate change and increasing frequencies of extreme events, future responses to climate change seem likely.